Bicycle speed indicator

ABSTRACT

A speed indicator for bicycles for indicating the shifting action of the bicycle and a speed sign at each state of shift includes a driving wheel driven by a takeup reel of a shifting device, a resilient strip driven by the driving wheel, and a track along which the resilient strip may displace. When the resilient strip displaces along the track, a shift sign pre-formed on the resilient strip may be shown through an indicating element provided on the track. The resilient strip may be adapted for use in vertically or horizontally oriented tracks of any construction, and their assembly is easy. The driving wheel further includes a compensation mechanism for ensuring clear indication of the indicated sign on the resilient strip.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a speed indicator, and moreparticularly to a speed indicator adapted for use in bicycle speedcontrol apparatuses which control the shifting devices.

2. Description of the Prior Art

Mounting a speed control apparatus on the handlebars of a bicycle forcontrolling the shifting actions of the bicycle is a known art. As theuse of the speed control apparatus in shifting the winding member doesnot allow the cyclist to exactly know the control situation, there aresome inventions which disclose mounting of a speed indicator on thespeed control apparatus to indicate the speed of the bicycle.

One such speed indicator is described in U.S. Pat. No. 5,012,692 toNagano. In FIG. 8 of said patent, a speed indicator resembling a ring isillustrated, but it is not described in detail in the disclosure. InU.S. Pat. No. 5,325,735, also issued to Nagano, a shifting device with atakeup reel is disclosed. A disc-like speed indicator of the shiftingdevice connected to a crown gear is disposed on the takeup reel, and thecrown gear is caused to engage with a coaxial gear so that the disc-likespeed indicator is driven via a tension pulley. Such a speed indicatoras taught in U.S. Pat. No. 5,325,735 is complicated in construction. Andbesides, as a pointer is used to indicate the numerical signs,misreading may easily occur.

There is another problem with the conventional shifting devices mountedon the handlebars of bicycles. In the conventional shifting deviceconsisting of a speed control cable wound around the takeup reel, sincethe diameter of each gear does not increase in a uniformly gradualmanner, when the speed control cable is wound by the takeup reel, thedistance displaced by the shifting lever between any two adjacent shiftsis not uniform, hence the distance between any two adjacent shiftsindicated by the speed indicator will also vary. For instance, supposingthe distance displaced by the speed indicator from the first shift signto the second shift sign is 5 mm, then the distance displaced by thespeed indicator from the second shift sign to the third shift sign maybe 6 mm, and that from the third shift sign to the fourth shift sign maybe 7.2 mm. The speed thus indicated by the speed indicator is notprecise. Solution to this problem is therefore necessary.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide a speedindicator for use in bicycle speed control apparatus, which has simpleconstruction and clear indication of speed, and which is adapted for usein vertically or horizontally oriented tracks or rails provided withindication signs or windows.

Another object of the present invention is to provide a speed indicatorwhich has a displacement compensation mechanism whereby, after ashifting lever pushes a takeup reel to move a shift indicating plate,the displacement distance between every two adjacent shifts is indicatedto be substantially the same.

According to the present invention, the speed indicator comprises adriving wheel driven by a takeup reel of a shifting device, a resilientstrip driven by the driving wheel, and a track along which the resilientstrip moves. When the resilient strip displaces along the track, a shiftcode pre-formed on the resilient strip is indicated via an indicatingelement attached to the track. The resilient strip may be adapted foruse in any vertically or horizontally oriented track and it may bemounted with convenience. The driving wheel further consists of acompensation mechanism which enables clearer and more precision speedindication by means of the resilient strip in the track.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features and advantages of the present inventionwill be more clearly understood from the following detailed descriptionand the accompanying drawings, in which,

FIG. 1 is a perspective view of a preferred embodiment of the presentinvention, showing a speed indicator with a vertical indication cover;

FIG. 2 is a perspective view of the preferred embodiment of the presentinvention shown in FIG. 1, illustrating the internal construction of thepreferred embodiment in an assembled state;

FIG. 3 is a perspective view of the resilient strip;

FIG. 4 is a perspective view of another preferred embodiment of theresilient strip;

FIG. 5 is a perspective view of the present invention in an assembledstate, showing use of a second preferred embodiment of the resilientstrip of FIG. 4, which has a horizontal indication cover;

FIG. 6 is a perspective outer view of the embodiment of the presentinvention shown in FIG. 5;

FIG. 7 is a partially sectional view taken along line 7--7 of FIG. 6;and

FIG. 8 is an elevational view of a third preferred embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The bicycle speed indicator according to the present invention may beused to indicate the situation in which bicycle transmission chains isselectively engaged with one of the gears of a freewheel gear cluster onthe hub. A preferred embodiment of the speed indicator of the presentinvention as shown in FIGS. 1, 2, 5 and 6 essentially comprises adriving wheel 5, a resilient strip 11, and a track for guiding theresilient 11 strip to displace along a pre-determined path; the track inthis preferred embodiment is an indication cover 9. The driving wheel 5is coupled to a takeup reel 4 disposed within a shifting device 2mounted on a handlebar 1 and turns with the takeup reel 4. When ashifting lever 3 is pushed, the takeup reel 4 will turn to pull orrelease a cable 8. The cable 8 is provided to actuate the shiftingdevice 2 on the bicycle frame so that a driving chain engages with Oneof the gears of the freewheel gear cluster to achieve the effect ofchanging the speed of the bicycle. As such shifting mechanism is wellknown in the art, it will not be described in detail herein.

The above-mentioned track may be an open one or a closed one, such asthe indication cover 9 shown in the drawings. The track is configured tohave a specific path for guiding the displacement of the resilient strip11 and an indicating element, such as a bulging arrow mark, a singlewindow, or multiple windows, for indicating or displaying one of aseries of numerals or a mark formed on the resilient strip 11.

The track adopted in this preferred embodiment is the indication cover 9shown in FIG. 1. The indication cover 9, fixed onto the handlebar 1, hasa window 10, which is one of the preferred embodiments of the indicatingelement provided on the track. The resilient strip 11 is marked thereona sign or signs S, such as the Arabic numerals 1 to 7 in FIGS. 2 and 3,or an easily recognizable mark in FIG. 4. The resilient strip 11 has apart thereof coupled to the driving wheel 5 and is driven thereby. Andbesides, one end of the resilient strip 11 may movably penetrate intothe indication cover 9 to expose the sign or signs S thereon through thewindow 10.

The resilient strip 11 according to the present invention permits simpleconstruction and assembly of the speed indicator. FIGS. 3 and 4respectively show two preferred embodiments of the resilient strip 11.Referring to FIGS. 1, 2, 5 and 6, the sign or signs S on the resilientstrip 11 may be a series of Arabic numerals (as in FIGS. 2 and 3), andrelatively, the indication cover 9 has only a single window 10, so thatonly one number, such as 1, or 2, or 3 . . . may be displayed throughthe window 10 at any given time. With reference to FIGS. 4 and 5 inwhich the resilient strip 11 is provided with only a mark, such as aquadrilateral mark of any color, the indication cover 9 may then beprovided with a plurality of juxtaposed windows with a series of Arabicnumerals, such as 1, 2, 3 . . . respectively marked thereabove, so thatthe mark is shown through one of the windows 10. No matter whether aseries of numerals or a single mark is provided on the resilient strip11 as the signs or sign S, fluorescent material may be adopted to formthe signs or sign S. The Arabic numerals shown above the windows 10 inFIG. 6 may also be formed by fluorescent materials. In this way, even ina dim environment, the cyclist can still clearly read the indicatednumerals. Nonetheless, one end of the resilient strip 11 may movablypenetrate into the indication cover 9 and displace with the indicationcover 9 i.e., the track, along a vertical or horizontal path.

A preferred embodiment showing the manner of coupling the resilientstrip 11 to the driving wheel 5 is illustrated in FIGS. 2 and 3. Thedriving wheel 5 has at least a part thereof provided with teeth 6, andthe resilient strip 11 has corresponding teeth 13 provided at, forinstance, a lateral rim thereof, for engaging with the teeth 6 of thedriving wheel 5. Although the indication cover 9 may be configured to bean elongated box structure (not shown), it is preferably a curved one.In FIG. 1, the indication cover 9 is mounted substantiallyperpendicularly to the handlebar 1.

In FIGS. 4 and 5, the resilient strip 11 is shown to have a series ofholes 12, which may engage with teeth 6 of the driving wheel 5 (see FIG.7). When the driving wheel 5 rotates with the takeup reel 4, theresilient strip 11 will be pushed by the driving wheel 5 to move in theindication cover 9 along a pre-determined path. Those skilled in the artshould understood that there are numerous ways of connecting the drivingwheel 5 and the resilient strip 11, and that their manner of connectionis not limited to the two ways described above. Another example ofconnecting the driving wheel 5 and the resilient strip 11 is shown inFIG. 8. In this example, the driving wheel 5 has a rim 51, and theresilient strip 11 has one end thereof directly fixed to the rim 51 ofthe driving wheel 5. When the resilient strip 11 is pressed by a means(e.g., an urging element 14 urged by a spring 15), the resilient strip11 has at least a part thereof in close contact with the rim 51 of thedriving wheel 5.

Reference is made to FIG. 8 in which a cam is adopted as an embodimentof the driving wheel 5. The rim 51 may consist of a plurality of variouscurved and segmented flanges or planes joined together. When the rim 51of the cam is formed by different contiguous surfaces (planes) connectedtogether, as shown in FIG. 8, and when the included angles e.g. A, B, Care the same, the lengths of their corresponding arcs, i.e., L, M, N aredifferent. Conversely, when the lengths of the arcs L, M, N are thesame, their corresponding included angles A, B, C are different. Asdescribed above, the takeup reel 4 will rotate through a different angleat each shifting action, so that the driving wheel 5 (cam) rotatingcoaxially with the takeup reel 4 will also rotate through a differentangle at each shifting action. By utilizing the above-mentionedcharacteristic of the cam, the lengths of the arcs of the cam may becaused to be the same at each shifting action when the rotational anglesof the takeup reel 4, hence the driving wheel 5 (cam), are different.The resilient strip 11 is fixed onto the rim 51 of the cam and isadhered thereto. Since the length of the arc corresponding to therotational (included) angle of the cam at each shifting is the same,every time when the resilient strip 11 follows the cam to rotatetherewith relative to the window 10 of the track, the displaced distancethereby will be the same. The resulting effect is that, when there isprovided only a single window 10, the numerals marked on the resilientstrip 11 may be arranged to be equi-distant from each other, without theneed to space them apart from each other at specific distance as in theprior art. On the other hand, when there are provided a plurality ofwindows 10 (and the resilient strip 11 relatively has only a sign S),the windows 10 may be arranged at equi-distance from each other,eliminating the need to arrange them at specific distance from eachother as in the prior art.

Although the present invention has been illustrated and described withreference to the preferred embodiments thereof, it should be understoodthat it is in no way limited to the details of such embodiments, but iscapable of numerous modifications within the scope of the appendedclaims.

What is claimed is:
 1. A bicycle speed indicator for displayingselective engagement of a transmission chain of a bicycle with one of aplurality of gears of a freewheel gear cluster provided on a hub of thebicycle, said speed indicator comprising:a driving wheel for coupling toa takeup reel of the bicycle for accommodating within a shifting devicemounted on a handlebar of the bicycle, said driving wheel for rotatingwith the takeup reel; a track having an indicating element and apre-determined guide path, said track for being fixed onto saidhandlebar of the bicycle; and a resilient strip having sign meanscorresponding to a shifting state of the bicycle, said resilient stripcoupled to said driving wheel and being driven thereby, said resilientstrip having a first end thereof movably inserted into said track tomove along said pre-determined guide path, said sign means and saidindicating element capable of alignment to display the shifting state ofthe bicycle; wherein said driving wheel is a cam, said cam has a rim andsaid resilient strip is fixed onto said rim at a second end of saidresilient strip and is urged against by a means such that at least afirst part of said resilient strip adheres to said rim, said first partof said resilient strip being spaced apart from said second end.
 2. Abicycle speed indicator as claimed in claim 1, wherein said track is acurved structure.
 3. A bicycle speed indicator as claimed in claim 1,wherein said track is configured for substantially perpendicularattachment to said handlebar of the bicycle.
 4. A bicycle speedindicator as claimed in claim 1, wherein said resilient strip movesalong a substantially horizontal path.
 5. A bicycle speed indicator asclaimed in claim 1, wherein said track is provided in the form of anindicator cover which at least partially encloses said resilient stripand said driving wheel.
 6. A bicycle speed indicator as claimed in claim5, wherein said indicator cover has at least a window which forms atleast part of said indicating element.
 7. A bicycle speed indicator asclaimed in claim 1, wherein said sign means on said resilient strip ismade of fluorescent material.
 8. A bicycle with a speed indicator fordisplaying selective engagement of a transmission chain of the bicyclewith one of a plurality of gears of a freewheel gear cluster provided ona hub of the bicycle, said bicycle comprising:a takeup wheelaccommodated within a shifting device mounted on a handlebar of saidbicycle; a driving wheel which is coupled to said takeup reel androtates therewith; a track having an indicating element and apre-determined guide path, said track being fixed onto said handlebar ofthe bicycle; and a resilient strip having sign means corresponding to ashifting state of the bicycle, said resilient strip coupled to saiddriving wheel and being driven thereby, said resilient strip having afirst end thereof movably inserted into said track to move along saidpre-determined guide path, said sign means and said indicating elementcapable of alignment to display the shifting state of the bicycle;wherein said driving wheel is a cam, said cam has a rim and saidresilient strip is fixed onto said rim at a second end of said resilientstrip and is urged against by a means such that at least a first part ofsaid resilient strip adheres to said rim, said first part of saidresilient strip being spaced apart from said second end.
 9. A bicycle asclaimed in claim 8, wherein said track is a curved structure.
 10. Abicycle as claimed in claim 8, wherein said track is substantiallyperpendicular to said handlebar of the bicycle.
 11. A bicycle as claimedin claim 8, wherein said resilient strip moves along a substantiallyhorizontal path.
 12. A bicycle as claimed in claim 8, wherein said signmeans on said resilient strip is made of fluorescent material.
 13. Abicycle as claimed in claim 8, wherein said track is provided in theform of an indicator cover which at least partially encloses saidresilient strip and said driving wheel.
 14. A bicycle as claimed inclaim 13, wherein said indicator cover has at least a window which formsat least part of said indicating element.